Union: Border agents opened fire on each other

The head of the Border Patrol agents union said the agent killed last week in a shooting in southern Arizona apparently opened fire on two fellow agents thinking they were armed smugglers and was killed when they returned fire.

National Border Patrol Council President George McCubbin said Sunday that the two sets of agents approached an area where a sensor had been activated. He says they arrived from different directions early Tuesday when Agent Nicholas Ivie opened fire.

Acting Cochise County Sheriff Rod Rothrock confirmed the scenario but would not say if Ivie was the first to shoot.

The shooting happened a few miles north of the border with Mexico, in a well-known smuggling area.

Tucson attorney Sean Chapman confirmed with CBS 5 News on Tuesday that he is representing the male agent involved in the border patrol shooting.

Chapman said that the U.S. Customs and Border Protection union asked him to represent the agent, not the agent himself. Chapman said this is standard procedure.

Chapman said he's been with the agent through every step of questioning by federal authorities.

Chapman said the incident has been "tragic for everyone." He said the agent who fired is "really broken up" about the fatal shooting.

Chapman doesn't believe any charges will be filed.

The FBI announced Friday that the shooting appeared to be a case of friendly fire.

Stay with cbs5az.com and CBS 5 News for updates on this developing story.

Pittsburgh Steelers offensive tackle and former Army Ranger Alejandro Villanueva (78) stands outside the tunnel alone during the national anthem before an NFL football game against the Chicago Bears, Sunday, Sept. 24, 2017. (AP Photo/Nam Y. Huh)

The Pittsburgh Steelers will be on the field during the national anthem for next weekend's game against the Baltimore Ravens.